Can I ground my preamp?


I have monoblocs each w/their own grounded cord and a preamp w/o a grounded cord. The problem is that I'm getting a slight ground hum from each amp. The amp manual says if this happens to use a cheater plug on the amps and to ground "at least one other component." Is it possible to ground my preamp, and if so how? Many thanks for any advice.
bojack
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I used to have this problem with big Parasound amps, and the cheater plugs actually did cure the problem. Didn't have to ground any other components, either
The preamp, being the heart of the system, should be grounded. The amps, for safety reasons, should be too, but for audio reasons (ground loop prevention) they should not. If the amps hum when grounded through the AC cords, it indicates that the manufacturer has not done their grounding homework (it is possible to have the amps grounded and **not** hum at the same time)- so the best method probably is to float the grounds of the AC cords with cheaters.

At any rate the preamp *should* be grounded, although I suspect it already is since you are getting the hum.
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